Fatty acid alkyl amides and dialkyl amides are used for various applications such as environmentally friendly solvents and as manufacturing aid for polymers. Processes for manufacturing of such amides are known in the art. Many of them start off from a carboxylic acid or a derivative such as the respective halide or ester and an alkyl or dialkyl amide. However, several drawbacks can be observed. Carboxylic acid halides, however, are expensive, and they tend to cleave off hydrogen halides during various occasions such as storing, transport, and reactions. Such halides are highly corrosive, and during the amide formation they need to be neutralized, either by one equivalent of amine or by an added base which may also react with carboxylic acid halide instead.
During formation of amides from esters (or lactones) and amines, alcohols will be formed, reducing the corrosion problem described above, see, e. g., WO 2010/037776. However, esters and lactones are usually quite expensive compared to carboxylic acids.
In US 2009/0062565, a process is disclosed in which fatty acid amides are being produced from the respective carboxylic acid and an amine. The process disclosed makes use of a two-reactor system. The water formed is being distilled off together with amine, and after a separation the amine can be recycled by introducing it into acid in order to start the amide formation reaction. However, for this process, usually an excess of amine is needed. This is particularly disadvantageous for small scale production and discontinuous processes.